We all know by now that, normally, four English clubs qualify for the Champions League and these are, normally, the same four that finish in the Premier League’s top four places.

Like we say, normally. The success of Manchester City and Liverpool in Europe, in conjunction with their shaky league form, raises a number of possibilities and permutations. We're going to try and explain them.

Abacuses at the ready. As Walter Sobchak once said, "you are entering a world of pain"...

What if a team wins the Champions League or Europa League?

If a team wins the Champions League, they qualify for the following season's Champions League group stages automatically, regardless of where they have finished in their domestic league.

If a team wins the Europa League, they also qualify for the following season’s Champions League. The stage at which they enter depends on how the Champions League winners did domestically.

Clear as mud? OK. Let’s pretend Manchester City win this year’s Champions League and use that as an example…

If City finish 3rd or higher in the Premier League and win the Champions League this season, the Europa League winners will enter next season's Champions League at the group stage.

If City finish 4th or lower and win the Champions League this season, the Europa League winners go into the final qualifying round of next season's Champions League.

What if both Manchester City win the Champions League and Liverpool win the Europa League?

Both Manchester City and Liverpool would play in the Champions League.

England would have five teams in the competition – 1st to 3rd in the Premier League, plus City and Liverpool.

City would qualify for the group stage automatically. Liverpool would only qualify for the group stage automatically if City had finished 3rd in the league or higher.

What if both win in Europe but both finish outside of the top four?

Both would still qualify for the Champions League.

The 4th-placed team, probably either Manchester United or West Ham United, would drop out and play in the Europa League group stage.

So, as has been noted in recent days, Manchester City and Liverpool could, together, deny United a place at the top table of European football next season.